Merge pull request #4579 from mokalovesoulmate/develop

[ci skip] Fix a CI_Email documentation example
diff --git a/user_guide_src/source/libraries/email.rst b/user_guide_src/source/libraries/email.rst
index eadfcfd..0b38737 100644
--- a/user_guide_src/source/libraries/email.rst
+++ b/user_guide_src/source/libraries/email.rst
@@ -374,7 +374,7 @@
 			{
 				$this->email->to($address);
 				$cid = $this->email->attachment_cid($filename);
-				$this->email->message('<img src='cid:". $cid ."' alt="photo1" />');
+				$this->email->message('<img src="cid:'. $cid .'" alt="photo1" />');
 				$this->email->send();
 			}